1. Field of the Invention:
The present invention relates to solder extractors. More particularly, the present invention relates to an improved replaceable tip for a solder extractor.
2. Description of the Prior Art:
Repair of electronic equipment often involves the need to remove solder fillets and joints efficiently without otherwise affecting the circuit as a whole or the components therein. Generally speaking, solder extraction is done by applying the front end of a heated tubular element to a soldered area to melt the solder, then suction applied to the rear end of the tubular member draws the molten solder off into the tube.
Siegel, U.S. Pat. No. 3,392,897 discloses a solder extractor comprising a coaxial instrument of pencil type construction in which a tubular heated tip, a heat generating element, a molten solder receiving chamber, and a gripping handle are all disposed concentrically and/or in axial succession one to another, with an axial passageway front to rear for the flow of extracted solder. This coaxial pencil-type construction is taught to have a number of advantages in solder removal:
(1) the molten solder moves in a straight line thereby avoiding the possibility of blockage or wear at bend regions and providing a good suction effect from the vacuum source;
(2) the solder extractor as a whole is light and well-balanced, a pencil-like grip permitting close, accurate control of the heated tip with less danger of burn damage to the circuit and components at areas near the solder being removed;
(3) the solder extractor can be readily applied to work pieces that have nearby encumbrances such as upstanding circuit components; and
(4) radiation and convection heating effects on the work piece are minimized.
However, such prior art solder extractors utilize a straight tubular tip, which when utilized in a pencil-like grip, acts to cause molten solder to be drawn substantially parallel to the workpiece surface, e.g., the surface of a printed circuit board. This drawing of the solder along the surface of the workpiece may be disadvantageous, especially in the case of a circuit board have intricate and/or closely spaced circuits. Alternatively, the tubular tip may be held substantially perpendicular to the circuit board, to desirably draw the molten solder upward and away from the board, but this hand position produces operator fatigue and loss of stability.
Moreover, since the tubular tip of the prior art is held in place by a set screw disposed in the solder extractor for this purpose, replacement of the tip, when it becomes worn or fouled with solder, can result in mis-positioning of the tip causing fluctuations in the length of the projection of the tip from the body of the solder extractor. Such fluctuations can alter heating rates and cause lowered temperatures, when the tip projects too far from the solder extractor, or can cause undesired radiation and convective heating effects on the workpiece, due to the solder extractor heating element, when this tip does not project sufficiently from the solder extractor.